An electro-photographic image forming apparatus exposes a charged photosensitive drum to form an electrostatic latent image on a photosensitive member, electro-statically adsorbs a toner (a developer) into the exposed portion to form a toner image, and then transfers the toner image onto a recording sheet, thereby forming an image.
Moreover, as described in Japanese Publication JP-A-11-258959, a scorotron type charger for charging a photosensitive member is constituted by a charging wire extended in a parallel direction with an axial direction of a photosensitive drum and a grid electrode having a predetermined interval with the charging wire and disposed on the photosensitive member side. A high voltage is applied to the charging wire so that a stable corona discharge is generated and the photosensitive member is charged.